The Blue Devils B Drum and Bugle Corps is a junior field competition unit based in Concord, California that competes in DCI's Open Class.

The Blue Devils organization started the corps in 1968 as a cadet drum and bell corps to serve as a feeder for the now many-times world-champion Blue Devils when the A corps first converted to being a drum and bugle corps..In 1973, the younger corps also converted to drums and bugles and was split into the current BDB and BDC corps.

Initially, the unit was mostly a stay-close-to-home corps and travelled to DCI Championships only five times between 1977 and 2004. Since 2005, BDB has attended every DCI Championship. The corps is no longer considered to be a "feeder" corps, and it is treated as a stand-alone second corps of the sponsoring BD Performing Arts.

Blue Devils B won the DCI Open Class World Champuionships in 2009-11, 2014, and 2016. The corps has advanced to World Class prelims every year since 2011, and they have moved up to semifinals each year since 2013, finishing as high as 15th in 2014 and 2016. Although the Blue Devils "A" corps have won consecutive DCI World Championships five times through 2017, they have never been able to accomplish a "three-peat" the way the "B" corps did in 2009-'10-'11.